Terphthalic acid

Hercules Chemical produced an acidic organic waste derived from the manufacture of dimethyl terphthalate, which is used in the production of synthetic liber. The average dissolved organic carbon concentration was about 7100 mg/L and included acetic acid, formic acid, p-toluic acid, formaldehyde, methanol, terphthalic acid, and benzoic acid. The pH ranged from 3.5 to 4.0. The waste also contained traces (less than 0.5 mg/L) of 11 other organic compounds, including dimethyl phthalate, a listed hazardous waste. 

PET is a polyester formed from terphthalic acid and ethylene glycol. 

Recently, we investigated the associative alkylation reaction of toluene with methanol catalyzed by an acidic Mordenite (see Figures 13 and 14) by means of periodic ab initio calculations." We observed that for this reaction some transition selectivity occurred, and induced sufficiently large differences in activation energies to explain the small changes in the para/meta/ortho distribution experimentally observed on large pore zeolites. Thepara isomer is the more valuable product as it is an important intermediate for terphthalic acid, an important polymer monomer." The steric constraints obtained for the transition state structures could be estimated from local intermediates for which the orientations of the toluene molecule were similar as the ones observed for the transition states (see Figure 14). 

Purified terphthalic acid EniChem/Technimont MMlb/y 350 700 10.599 0.6... 

Polyethylene Terphthalate - A family of plastics based on polymerization of an ester of diethylene glycol and terphthalic acid. 

MAJOR USES Manufacture of dyes, varnishes, resins, ethyl benzene, benzoic acid, hydrogen peroxide, terphthalic acids, organic chemicals, paint, polyester fibers, solvents, perfumes, insect repellents and pharmaceuticals. 

MAJOR USES Used in the production of benzoic acid, phthalic anhydride, isophthalic and terphthalic acids, polyester fibers, solvents, dyes and paints and coatings clearing agent in microscopic technique blended into gasoline. 

SPIOOO (Supelco Inc.), a polyethylene glycol substituted terphthalic acid, on 100-120 inert diatomite (AW, DCDMS) support for US EPA method 612 for chlorinated hydrocarbons ... 

As already mentioned, the hydrolytic stability of polyurethanes is influenced by the nature of the macroglycol used in their preparation. Polyesters prepared from sterically hindered glycols, such as neopentyl glycol (18), and a long-chain diacid, or aromatic diacid, for example, terphthalic acid (19), will maximize moisture stability. Polyester polyols have been developed which are claimed to be similar in hydrolytic stability to PTMO polyurethanes. Increasing the crosslink density in polyester polyurethanes has been shown to improve hydrolytic stability as well however, this may not always be a viable solution, since the crosslink density can have a profound influence on other properties of the polymers as already described. 

TABLE 1. Char Formation of Polyethylene Terphthalate Modified with 5-sodiosulfoisophthalic Acid... 

Vectra A is a commercially available polymer from Hoechst-Celanese. It is a random co-polyester of hydroxy benzoic acid (HBA) and hydroxy napthoic acid (HNA), which is a well-known class of thermotropic liquid crystalline polymer (TLCP) [92-95]. Crystallization of molecules of TLCPs is considerably different from that of polymers like polyethylene or polyethylene terphthalate [1], TLCPs have reduced flexibility compared to the latter, which implies that large translations of their molecules are required for recrystallization [96-99],... 

Lee S H, Lim S W and Lee K H (1999) Properties of potentially biodegradable copolyesters of (succinic acid-1,4-butanediol)/(dimethyl terphthalate-l,4-butanediol), Polym Int 48 861-867. 

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